Merge pull request #10 from brainn-co/sl-rename-value

Add rename_value/4

README.md

@@ -25,7 +25,7 @@ The package can be installed by adding `ecto_enum_migration` to your list of dep
 ```elixir
 def deps do
   [
-    {:ecto_enum_migration, "~> 0.2.0"}
+    {:ecto_enum_migration, "~> 0.3.0"}
   ]
 end
 ```

lib/ecto_enum_migration.ex

@@ -181,6 +181,62 @@ defmodule EctoEnumMigration do
     |> execute_query()
   end
 
+  @doc """
+  Rename a value of a Postgres Type.
+
+  ## Examples
+
+  ```elixir
+  defmodule MyApp.Repo.Migrations.RenameTypeMigration do
+    use Ecto.Migration
+    import EctoEnumMigration
+
+    def change do
+      rename_value(:status, :finished, :done)
+    end
+  end
+  ```
+
+  By default the type will be created in the `public` schema.
+  To change the schema of the type pass the `schema` option.
+
+  ```elixir
+  rename_value(:status, :finished, :done, schema: "custom_schema")
+  ```
+
+  """
+  @spec rename_value(
+          type_name :: atom(),
+          before_value :: atom(),
+          after_value :: atom(),
+          opts :: Keyword.t()
+        ) :: :ok | no_return()
+
+  def rename_value(type_name, before_value, after_value, opts \\ [])
+      when is_atom(type_name) and is_atom(before_value) and is_atom(after_value) and is_list(opts) do
+    type_name = type_name(type_name, opts)
+    before_value = to_value(before_value)
+    after_value = to_value(after_value)
+
+    up_sql = "
+      UPDATE pg_catalog.pg_enum
+      SET enumlabel = #{after_value}
+      WHERE enumtypid = '#{type_name}'::regtype::oid
+        AND enumlabel = #{before_value}
+      RETURNING enumlabel;
+    "
+
+    down_sql = "
+      UPDATE pg_catalog.pg_enum
+      SET enumlabel = #{before_value}
+      WHERE enumtypid = '#{type_name}'::regtype::oid
+        AND enumlabel = #{after_value}
+      RETURNING enumlabel;
+    "
+
+    execute(up_sql, down_sql)
+  end
+
   defp before_after(opts) do
     before_value = Keyword.get(opts, :before)
     after_value = Keyword.get(opts, :after)

mix.exs

@@ -4,7 +4,7 @@ defmodule EctoEnumMigration.MixProject do
   def project do
     [
       app: :ecto_enum_migration,
-      version: "0.2.0",
+      version: "0.3.0",
       elixir: "~> 1.7",
       start_permanent: Mix.env() == :prod,
       deps: deps(),

test/ecto_enum_migration_test.exs

@@ -76,6 +76,24 @@ defmodule EctoEnumMigrationTest do
     end
   end
 
+  defmodule RenameValueMigration do
+    use Ecto.Migration
+    import EctoEnumMigration
+
+    def change do
+      rename_value(:status, :registered, :filled)
+    end
+  end
+
+  defmodule RenameValueWithCustomSchemaMigration do
+    use Ecto.Migration
+    import EctoEnumMigration
+
+    def change do
+      rename_value(:status, :registered, :filled, schema: "custom_schema")
+    end
+  end
+
   defmodule AddValueToTypeMigration do
     use Ecto.Migration
     import EctoEnumMigration
@@ -383,6 +401,50 @@ defmodule EctoEnumMigrationTest do
     end
   end
 
+  describe "rename_value/4" do
+    test "renames value" do
+      create_version = version_number()
+      rename_version = version_number()
+
+      :ok = up(create_version, CreateTypeMigration)
+      :ok = up(rename_version, RenameValueMigration)
+
+      assert current_types() == %{
+               "public.status" => ["filled", "active", "inactive", "archived"]
+             }
+
+      :ok = down(rename_version, RenameValueMigration)
+
+      assert current_types() == %{
+               "public.status" => ["registered", "active", "inactive", "archived"]
+             }
+
+      :ok = down(create_version, CreateTypeMigration)
+    end
+
+    test "supports custom schema" do
+      :ok = up(version_number(), CreateSchemaMigration)
+
+      create_version = version_number()
+      rename_version = version_number()
+
+      :ok = up(create_version, CreateTypeWithCustomSchemaMigration)
+      :ok = up(rename_version, RenameValueWithCustomSchemaMigration)
+
+      assert current_types() == %{
+               "custom_schema.status" => ["filled", "active", "inactive", "archived"]
+             }
+
+      :ok = down(rename_version, RenameValueWithCustomSchemaMigration)
+
+      assert current_types() == %{
+               "custom_schema.status" => ["registered", "active", "inactive", "archived"]
+             }
+
+      :ok = down(create_version, CreateTypeWithCustomSchemaMigration)
+    end
+  end
+
   defp up(version, migration) do
     Ecto.Migrator.up(TestRepo, version, migration, log: false)
   end